National Public Radio: Clean energy has become the mantra of Silicon Valley venture capitalists. The centerpiece has been the electric car, principally the Tesla Roadster, a sleek, expensive sports car out this year. While the economic meltdown has put a crimp in their plans for sales growth, electric-car manufacturers hope for a thin slice of the $25 billion auto industry bailout being considered by Congress. Though Tesla Motor Inc.’s Roadster is quiet, it has not gone unnoticed by the automotive world. …